Atigun Pass closure highlights North Slope’s fragile road access

A five-mile closure near Atigun Pass again showed how little margin the North Slope has when the Dalton Highway is interrupted. Alaska’s 511 system reported avalanche mitigation work from milepost 242 to milepost 247, a short shutdown that still touched the only road lifeline serving freight, fuel and heavy equipment headed north.

That matters because the Dalton runs 414 miles from Livengood to Deadhorse and carries most of its traffic from commercial trucks delivering supplies and fuel to North Slope oil fields. When the road closes, hauling schedules can slip, worker rotations can be delayed and time-sensitive cargo can pile up behind a single mountain corridor that is exposed to steep terrain and fast-changing weather.

The Alaska Department of Transportation and Public Facilities has built a year-round safety system around that corridor. DOT&PF operates seven maintenance camps along the highway, with each camp covering about 60 to 70 miles, and spends about $16.5 million a year maintaining the route. Its Snow Avalanche Programs use specially trained crews, along with artillery and other methods, to deliberately trigger slides before they threaten drivers and freight haulers.

Atigun Pass is especially vulnerable. DOT research says the pass sits in a corridor with more than forty avalanche paths and about half a dozen slushflow gullies. The highway, built in 1974 during construction of the Trans-Alaska Pipeline, was designed for a rugged mountain crossing that has never been easy to keep open. A January 1993 slide buried more than 600 meters of road and involved several vehicles, a reminder of why the state shifted to proactive avalanche forecasting and control.

The June closure also followed a severe weather advisory for the Central Brooks Range. National Weather Service Fairbanks issued Avalanche Weather Guidance for Atigun Pass high elevations on June 4, and the forecast called for 5 to 10 inches of snow with wind gusts up to 30 mph through Monday evening. DOT says highway avalanches usually peak between December and March, but they can happen as late as June.

The North Slope Borough, which covers nearly 95,000 square miles in northern Alaska, depends on that road for industrial support and basic supply lines to places such as Prudhoe Bay and Deadhorse. A 2025 flood that damaged and severed the Dalton, triggering a state disaster declaration, showed that avalanches are only one of several weather threats that can cut the region off. For communities and operators across the borough, the closure near Atigun Pass was not a routine traffic delay. It was a brief reminder that one mountain road still carries too much of the North Slope’s daily life.